The Portuguese Naval Aviation (Portuguese: Aviação Naval Portuguesa) is the naval air component of the Portuguese Navy, officially designated as Esquadrilha de Helicópteros da Marinha (EHM), responsible for the operation of the aircraft on board their ships.[7]

It is more commonly known as Naval Aviation as it received various official designations throughout its service and its origins date back to 1917, when it was created has the air branch of the Navy. The service was then disbanded and integrated into the Portuguese Air Force (PoAF), upon the creation of this new branch in 1952, having been reactivated in its current form in 1993 to operate the Navy's new shipborne helicopters entering service with the Vasco da Gama frigates.

The origins of the Portuguese Naval Aviation date back to 1916, when two Navy officers were sent to France to undergo flight training[8] as part of a larger effort started in 1913 to create a military aviation school capable of serving as the basis for the creation of both the Army's and Navy's aviation services.[9] These two Navy officers — 1TEN Artur de Sacadura Cabral and GMAR AN António Joaquim Caseiro — underwent basic flight training at Chartres and flying boat flight training at Saint-Raphaël, Var.[3][10][11]

During Sacadura Cabral's stay in France, he was also appointed by the Navy Ministry to establish contact with the French aviation industry to study the existing hydroplane models to equip a future Portuguese naval air service.[11]

Upon their return, both were appointed flight instructors at the Military Aviation School of Vila Nova da Rainha (Portuguese: Escola de Aviação Militar de Vila Nova da Rainha), the navy's section of the Army's School of Military Aeronautics (Portuguese: Escola de Aeronáutica Militar, EAM), with Sacadura Cabral being appointed instruction director.[10] Meanwhile, Navy personnel started receiving flight training and aircraft maintenance instruction at the school and abroad, in France.[8][12]

Also upon his return to Portugal, Sacadura Cabral was asked by the War Minister to designate an appropriate location for a future hydroplane naval air station, which later became the Bom Sucesso Naval Air Station (Portuguese: Centro de Aviação Naval do Bom Sucesso).

In late 1916, due to the threat posed by the submarines of the Imperial German Navy to the merchant ships sailing along the Portuguese coast during World War I, the French government asked Portugal permission to install a naval air station in Portugal.[8][13] 1st Lieutenant Maurice Larrouy, of the French Navy, elaborated a study which proposed the installation of an airship and hydroplane base in Lisbon, and two additional hydroplane bases in the north and south of Portugal. However, due to the logistics costs of operating airships, Sacadura Cabral opposed the plan of installing an airship base in Lisbon and instead the decision was made to equip Bom Sucesso with anti-submarine flying boats and to build a hydroplane base for the French Naval Aviation in Aveiro.[14]

On September 28, 1917, the Navy's Aviation Service (Portuguese: Serviço de Aviação da Armada) was created with its personnel, material and aviation school being separated from the Army's EAM.[1] The service was then installed at the Bom Sucesso Naval Air Station in the Lisbon docks.

Two F.B.A. flying boats, received in March 1917 and stored at EAM, arrived at Bom Sucesso by December 1917, marking the beginning of the Navy's independent flight operations.

On January 5, 1918, the naval aviation was renamed to Naval Aeronautical Service (Portuguese: Serviço da Aeronáutica Naval).[15]

Lieutenant-Commander Sacadura Cabral and Captain Gago Coutinho in the cockpit of the Fairey III seaplane Lusitânia, at the departure for the first aerial crossing of the South Atlantic.

In April 1918 the first flying boats of the French Navy arrived at São Jacinto, in Aveiro.[13] Together with the Portuguese aircraft at Bom Sucesso naval air station, this allowed them to perform anti-submarine patrols and cover the coastal Portuguese waters and the main ports.[14]

With the end of the war the Frency Navy left São Jacinto and handed over the naval air station to the Portuguese Navy as well as 18 Donnet-Denhaut D.D.8 and two Georges Levy G.L.40 flying boats as a gift. On December 28, 1918, a Portuguese Navy officer took command of the São Jacinto Naval Air Station (Portuguese: Centro de Aviação Naval de S. Jacinto).[13]

The United States Navy left as well their base at Horta and offered to the Portuguese Navy four Curtis HS-2L. These aircraft were transported and ship to Lisbon and started operating from Bom Sucesso in 1923.

In April 1931, following an attempted military takeover in Funchal, Madeira, the Portuguese government declares martial law in Madeira and in the Azores. Four CAMS 37A[17] of the Naval Aviation were then sent on April 11 to Horta, Madeira, by ship to perform reconnaissance, ground attack, and psychological warfare missions against the local revolting forces. These aircraft flew 100 hours and were hit by small arms fire and fireworks converted into rudimentary anti-aircraft rockets. Nevertheless, no aircraft were lost and all returned to Lisbon by the end of the hostilities.[8][16]

At this time, the Magalhães Corrêa naval modernization program (Portuguese: Plano Naval Magalhães Corrêa) included the purchase of a seaplane tender that was order from Italy in 1931. However, as consequence of the 1929 economic crisis, the value of the Lira collapsed and the increase of the acquisition costs led to the contract being canceled. Nevertheless, as part of the modernization program two 1st class avisos of the NRP Afonso de Albuquerque were built with the capacity to carry a floatplane, Hawker Osprey III. These aircraft were mostly used in reconnaissance and training and by the 1940s it was decided that they added didn't add any further capabilities to the ship and their facilities were replaced on the ships by anti-aircraft artillery.[18]

On September 30, 1936, the designation of the Naval Aviation was changed to Navy Air Forces (Portuguese: Forças Aéreas da Armada).[19]

Between 1939 and 1940 Avro 626, equipped with floats, and Grumman G-21B Goose were bought. During its service, the Grumman Goose established regular transport between continental Portugal to the Azores and performed search and rescue missions.[20]

In February 1941, a Short Sunderland was interned after being forced to land in the Portuguese coast, during to a flight from the United Kingdom to Gibraltar, due to high winds.

That same year, twenty de Havilland DH-82A Tiger Moth were transferred to the Portuguese Navy from a large batch bought by the Portuguese government and also received from the UK as compensation for the use of the aviation facilities in Azores.[8] These aircraft were found to be more economical for the flight training of new pilots, as most training accidents with float-planes resulted in the total loss of the airframe, and allowed to improve and expand the training at the "Almirante Gago Coutinho" Naval Aviation School, in Aveiro.[21]

In 1943, the Naval Aviation received former-Royal Air Force Bristol Blenheim bombers, while these aircraft had already been used extensively in combat, they were equipped with modern avionics and communication equipment which allowed the Portuguese Navy to familiarize their personnel with more modern combat aircraft. 12 Airspeed Oxford for flight and navigation training were also transferred to the Naval Aviation as part of the use of the aviation facilities in Azores by the UK. The first six aircraft were delivered in 1943 but the remaining aircraft were only delivered in 1947, after the end of the war.[22]

In 1945, a batch of Bristol Beaufighter TF.X were received also as part of the deal for the use of the Azores by the British during World War II. These aircraft improved greatly the combat capacity of the Naval Aviation but due to high maintenance costs were shortly after retired, with many aircraft still having many flight hours left.[23]

With the unification of the Army and Navy's military aviation services by the Under-Secretary of State for the Aeronautics (Portuguese: Subsecretariado de Estado da Aeronáutica), the Portuguese Air Force (PoAF) was created in 1952 and all Naval Aviation assets were transferred to this new branch. However, the naval aviation's units formed inside the Air Force a semi-independent branch for operational and training purposes designated Naval Air Forces (Portuguese: Forças Aeronavais). By 1958, with the anti-submarine and maritime patrol squadrons completely integrated into the Air Force, the Naval Aviation was finally disbanded and its last remaining technicians and officers returned to the Navy.[2][8][27]

In 1964, during the Ultramar War, a PoAF Alouette II made what is considered the first helicopter operation from a Portuguese Navy ship, by performing personnel transport and medical evacuation missions from a wooden platform constructed on the NRP Nuno Tristão, in Guinea. Later in the war other helicopter medical evacuations were made by PoAF helicopters to NRP Sam Brás.[18]

During the war and after the war Alouette III helicopters landed on the flight decks of the João Coutinho-class corvettes and NRP São Gabriel. In 1987, upon the modernization of the João Belo-class frigates, it was considered equipping them with a flight deck and a telescopic hangar to enable them to carry an organic anti-submarine helicopter. However, the modernization program continued without making these changes to the ships.[25]

In 1977, with the need to replace older ships in its fleet, the Portuguese Navy created a work group (Portuguese: Grupo de Trabalho de Actualização dos Meios Navais) to study the purchase of new ships, including new frigates.[28] This work group also proposed the acquisition of helicopters to equip the new frigates. However, mostly due to lack of funds, a decision wasn't made to acquire new equipment.

Finally in the middle of the 1980s, with the continuation of the Cold War and the need to modernize the naval fleet, a decision was made to purchase new frigates with the capacity to operate organic helicopters.[2] At the end of the decade of 1980, the Navy started evaluating both the Kaman SH-2 Seasprite and Westland Lynx as the frigate's on-board helicopters.[29] In August 1988 a group of officers were sent to Plymouth, United Kingdom to undergo the Air Engineer Application Course, at the Royal Naval Engineering College, to start receiving training in aerodynamics, shipborne aeronautical systems, engine maintenance, and the control and certification of all maintenance procedures. In April 1989 the officers continued their training at the HMS Daedalus, and later were divided into two groups and sent to receive their certifications at 829 Naval Air Squadron and 715 Naval Air Squadron of the Royal Navy Air Arm.[30][31]

Having returned to Portugal in October 1989, the officers that underwent training in the United Kingdom integrated a new work group for the acquisition of the naval helicopters (Portuguese: Grupo de Trabalho para a Aquisição dos Helicópteros, GTAH). In December 1989 the final decision was made to acquire five Westland Super Lynx Mk.95 helicopters.[30]

The Navy's Helicopter Squadron was officially created on June 2, 1993,[4] with the mission of training the helicopter maintenance personnel and on-board helicopter operations crews, support the flotilla, naval units and embarked helicopter detachments, and maintain two helicopter detachments.[3][7] The squadron was activated on June 8, 1993, and was based at the Montijo Air Base, with its facilities being inaugurated on September 24 of the same year and the first two helicopters having been delivered on July 29.[2][8]

In 1995, the first helicopter detachment was formed and started on-board operations. Currently, the Naval Aviation operates the Lynx helicopters from the Vasco da Gama-class and Bartolomeu Dias-class frigates.[2]

Since the reactivation of the Naval Aviation it was decided to use the available Air Force's logistics and training infrastructure to reduce costs and improve the overall unit performance.[2] As such, officers are selected from the Naval School and then undergo flight training at the Air Force on the Aérospatiale Epsilon TB-30 with 101 Squadron and later on the Aérospatiale Alouette III with 552 Squadron. Having completed their flight training in the Air Force, the naval pilots return to the Navy to start their operational conversion to the Lynx helicopter at the Helicopter Instruction Center (Portuguese: Centro de Instrução de Helicópteros, CIH) of the EHM.[32][33]

Lisbon Naval Aviation Centre: created in 1917 as a seaplane base located at the Bom Sucesso Docks, being the first operational naval aviation base. On January 2, 1953, it was transferred to its new facilities in Montijo that, besides a seaplane base, had an airfield, becoming officially designated as "Sacadura Cabral" Naval Aviation Centre. It was renamed as Air Base No. 6 on June 12, 1954.

Azores Naval Aviation Centre (Portuguese: Centro de Aviação Naval dos Açores, CANA): seaplane base installed in 1918 in Horta during World War I. In 1919 it was transferred to Ponta Delgada, being deactivated in 1921. The centre was reactivated in 1941 during World War II being definitely deactivated in 1946.[36]

Macau Naval Aviation Centre: seaplane base installed at the Taipa island in 1927 to support the naval forces that combated the piracy on the seas of China and the Chinese Civil War. The centre was deactivated in 1933 but was reactivated in 1937, by occasion of the Second Sino-Japanese War. In 1940 the centre was transferred to the new facilities constructed in the Exterior Port of Macau. In 1942 it was definitely deactivated.[37]

Algarve Naval Aviation Centre: seaplane base constructed in 1918, at the Culatra Island, on the coast of Faro and Olhão, during World War I, to operate anti-submarine flying boats. Although its hangars and main infrastructures were built, it wasn't officially activated, serving later its facilities as support for a Navy's maneuvers and instruction zone.

"Almirante Gago Coutinho" Naval Aviation School: activated in 1928 to allow the complete formation of the Naval Aviation personnel, which instruction was, until then, partially done in foreign aviation schools. It executed its functions at the Aveiro Naval Aviation Centre facilities until 1952.

B Squadron of the Navy Air Forces (Esquadrilha B das Forças Aéreas da Armada): land based naval attack bomber unit, dependent of the Lisbon Naval Aviation Centre, but based at the Lisbon Airport. Activated in 1942 and deactivated in 1949.